In this study, strong ground motion record (SGMR) selection based on Eta (~/) as a spectral shape indicator has been investigated as applied to steel braced flame structures. A probabilistic seismic hazard disaggr...In this study, strong ground motion record (SGMR) selection based on Eta (~/) as a spectral shape indicator has been investigated as applied to steel braced flame structures. A probabilistic seismic hazard disaggregation analysis for the definition of the target Epsilon (ε) and the target Eta (η) values at different hazard levels is presented, taking into account appropriately selected SGMR's. Fragility curves are developed for different limit states corresponding to three representative models of typical steel braced frames having significant irregularities in plan, by means of a weighted damage index. The results show that spectral shape indicators have an important effect on the predicted median structural capacities, and also that the parameter r/is a more robust predictor of damage than searching for records with appropriate c values.展开更多
Autonomous experimentation–or self-driving labs–offers a systematic approach to accelerate materials discovery by integrating automated synthesis,characterization,and data-driven decisionmaking.We present a closed-l...Autonomous experimentation–or self-driving labs–offers a systematic approach to accelerate materials discovery by integrating automated synthesis,characterization,and data-driven decisionmaking.We present a closed-loop workflow for the on-demand synthesis and structural characterization of colloidal gold nanoparticles,enabling direct mapping from composition to nanoscale structure.Our framework leverages differentiable models of spectral shape to address two central tasks in self-driving labs:(a)phase mapping,or identifying compositional regions with distinct structural behavior;and(b)material retrosynthesis,or optimizing compositions for target structure.Using functional data analysis,we develop a data-driven model with generative pre-training,active learning,and high-throughput experiments to predict spectral responses across composition space.We demonstrate the approach on seed-mediated growth of gold nanoparticles,showcasing its ability to extract design rules,reveal secondary interactions,and efficiently navigate morphology space.Gradient-based optimization of the models enables inverse design,making this a unified platform.展开更多
We demonstrated a scheme of bandwidth expansion and pulse shape optimized to afford 10 PW laser design via spec-tral shaping,which uses the existing Nd:glass amplifier chain of the SG PW laser.Compared to the amplifie...We demonstrated a scheme of bandwidth expansion and pulse shape optimized to afford 10 PW laser design via spec-tral shaping,which uses the existing Nd:glass amplifier chain of the SG PW laser.Compared to the amplified pulse with a gain-narrowing effect,the required parameters of injected pulse energy,spectral bandwidth,and shape are analyzed,to-gether with their influence on the system B-integral,energy output capability,and temporal intensity contrast.A bandwidth expansion to 7 nm by using LiNbO_(3) birefringent spectral shaping resulted in an output energy of 2 kJ in a proof-of-principle experiment.The results are consistent with the theoretical prediction which suggests that the amplifier chain of SG PW laser is capable of achieving 6 kJ at the bandwidth of 7 nm and the B-integral<π.This will support a 10 PW laser with a compressed pulse energy of 4.8 kJ(efficiency=80%)at 480 fs.展开更多
The dynamic characteristics of a beam-cable coupled system are investigated using an improved Chebyshev spectral element method in order to observe the effects of adding cables on the beam. The system is modeled as a ...The dynamic characteristics of a beam-cable coupled system are investigated using an improved Chebyshev spectral element method in order to observe the effects of adding cables on the beam. The system is modeled as a double Timoshenko beam system interconnected by discrete springs. Utilizing Chebyshev series expansion and meshing the system according to the locations of its connections, numerical results of the natural frequencies and mode shapes are obtained using only a few elements, and the results are validated by comparing them with the results of a finite-element method. Then the effects of the cable parameters and layout of connections on the natural frequencies and mode shapes of a fixed-pinned beam are studied. The results show that the modes of a beam-cable coupled system can be classified into two types, beam mode and cable mode, according to the dominant deformation. To avoid undesirable vibrations of the cable, its parameters should be controlled in a reasonable range, or the layout of the connections should be optimized.展开更多
We present a systematic analysis on the role of the quantum dot (QD) shape in the influence of the phonon bath on the dynamics of a QD cavity QED system. The spectral functions of the phonon bath in three representa...We present a systematic analysis on the role of the quantum dot (QD) shape in the influence of the phonon bath on the dynamics of a QD cavity QED system. The spectral functions of the phonon bath in three representative QD shapes: spherical, ellipsoidal, and disk, are calculated from the carrier wave functions subjected to the confinement potential provided by the corresponding shape. The obtained spectral functions are used to calculate three main effects brought by the phonon bath, i.e., the coupling renormalization, the off-resonance assisted feeding rate and the pure dephasing rate. It is found that the spectral function of a disk QD has the widest distribution, hence the phonon bath in a disk QD can lead to the smallest renormalization factor, the largest dephasing rate in the short time domains(≤2 ps), and the oft-resonance assisted feeding can support the widest detuning. Except for the pure dephasing rate in the long time domains, all the influences brought by the phonon bath show serious shape dependence.展开更多
By utilizing a Fabry–Perot (FP) nanocavity adjacent to T-shaped gap waveguide ports, spectrally selective filtering is realized. When the wavelength of incident light corresponds to the resonance wavelength of the ...By utilizing a Fabry–Perot (FP) nanocavity adjacent to T-shaped gap waveguide ports, spectrally selective filtering is realized. When the wavelength of incident light corresponds to the resonance wavelength of the FP nanocavity, the surface plasmons are captured inside the nanocavity, and light is highly reflected from this port. The resonance wavelength is determined by using Fabry–Perot resonance condition for the nanocavity. For any desired filtering frequency the dimension of the nanocavity can be tailored. The numerical results are based on the two-dimensional finite difference time domain simulation under a perfectly matched layer absorbing boundary condition. The analytical and simulation results indicate that the proposed structure can be utilized for filtering and splitting applications.展开更多
文摘In this study, strong ground motion record (SGMR) selection based on Eta (~/) as a spectral shape indicator has been investigated as applied to steel braced flame structures. A probabilistic seismic hazard disaggregation analysis for the definition of the target Epsilon (ε) and the target Eta (η) values at different hazard levels is presented, taking into account appropriately selected SGMR's. Fragility curves are developed for different limit states corresponding to three representative models of typical steel braced frames having significant irregularities in plan, by means of a weighted damage index. The results show that spectral shape indicators have an important effect on the predicted median structural capacities, and also that the parameter r/is a more robust predictor of damage than searching for records with appropriate c values.
基金funded primarily by the US Department of Energy (DOE), Office of Science, and Office of Basic Energy Sciences (BES) under award number DE-SC0019911Funding for H.T.C. was provided through the Energy Frontier Research Centers program: CSSAS—The Center for the Science of Synthesis Across Scales—under Award Number DE-SC0019288+2 种基金A.G. was supported by the University of Washington Molecular Engineering Materials Center (MEM-C, NSF grant DMR-2308979) as a part of the Academic Year Research Acceleration Research Experience for Undergraduates program. This work was also facilitated by the advanced computational, storage, and networking infrastructure provided by the Hyak supercomputer system and the Department of Chemical Engineering at the University of Washington. Part of this work was conducted at the Molecular Analysis Facility, a National Nanotechnology Coordinated Infrastructure (NNCI) site at the University of Washingtonsupported in part by funds from the National Science Foundation (awards NNCI-2025489, NNCI-1542101)the Molecular Engineering & Sciences Institute, and the Clean Energy Institute.
文摘Autonomous experimentation–or self-driving labs–offers a systematic approach to accelerate materials discovery by integrating automated synthesis,characterization,and data-driven decisionmaking.We present a closed-loop workflow for the on-demand synthesis and structural characterization of colloidal gold nanoparticles,enabling direct mapping from composition to nanoscale structure.Our framework leverages differentiable models of spectral shape to address two central tasks in self-driving labs:(a)phase mapping,or identifying compositional regions with distinct structural behavior;and(b)material retrosynthesis,or optimizing compositions for target structure.Using functional data analysis,we develop a data-driven model with generative pre-training,active learning,and high-throughput experiments to predict spectral responses across composition space.We demonstrate the approach on seed-mediated growth of gold nanoparticles,showcasing its ability to extract design rules,reveal secondary interactions,and efficiently navigate morphology space.Gradient-based optimization of the models enables inverse design,making this a unified platform.
基金Projectsupported by the International Partnership Program of Chinese Academy of Sciences(Grant No.181231KYSB20170022)the Natural Science Foundation of Jiangsu Higher Education Institutions of China(Grant No.20KJB140020).
文摘We demonstrated a scheme of bandwidth expansion and pulse shape optimized to afford 10 PW laser design via spec-tral shaping,which uses the existing Nd:glass amplifier chain of the SG PW laser.Compared to the amplified pulse with a gain-narrowing effect,the required parameters of injected pulse energy,spectral bandwidth,and shape are analyzed,to-gether with their influence on the system B-integral,energy output capability,and temporal intensity contrast.A bandwidth expansion to 7 nm by using LiNbO_(3) birefringent spectral shaping resulted in an output energy of 2 kJ in a proof-of-principle experiment.The results are consistent with the theoretical prediction which suggests that the amplifier chain of SG PW laser is capable of achieving 6 kJ at the bandwidth of 7 nm and the B-integral<π.This will support a 10 PW laser with a compressed pulse energy of 4.8 kJ(efficiency=80%)at 480 fs.
基金supported by the National Basic Research Program of China (Grant 2013CB733004)
文摘The dynamic characteristics of a beam-cable coupled system are investigated using an improved Chebyshev spectral element method in order to observe the effects of adding cables on the beam. The system is modeled as a double Timoshenko beam system interconnected by discrete springs. Utilizing Chebyshev series expansion and meshing the system according to the locations of its connections, numerical results of the natural frequencies and mode shapes are obtained using only a few elements, and the results are validated by comparing them with the results of a finite-element method. Then the effects of the cable parameters and layout of connections on the natural frequencies and mode shapes of a fixed-pinned beam are studied. The results show that the modes of a beam-cable coupled system can be classified into two types, beam mode and cable mode, according to the dominant deformation. To avoid undesirable vibrations of the cable, its parameters should be controlled in a reasonable range, or the layout of the connections should be optimized.
基金supported by the National Natural Science Foundation of China(Grant No.10974072)
文摘We present a systematic analysis on the role of the quantum dot (QD) shape in the influence of the phonon bath on the dynamics of a QD cavity QED system. The spectral functions of the phonon bath in three representative QD shapes: spherical, ellipsoidal, and disk, are calculated from the carrier wave functions subjected to the confinement potential provided by the corresponding shape. The obtained spectral functions are used to calculate three main effects brought by the phonon bath, i.e., the coupling renormalization, the off-resonance assisted feeding rate and the pure dephasing rate. It is found that the spectral function of a disk QD has the widest distribution, hence the phonon bath in a disk QD can lead to the smallest renormalization factor, the largest dephasing rate in the short time domains(≤2 ps), and the oft-resonance assisted feeding can support the widest detuning. Except for the pure dephasing rate in the long time domains, all the influences brought by the phonon bath show serious shape dependence.
基金Project supported by the National Key Basic Research Program of China (Grant No. 2013CB328702)
文摘By utilizing a Fabry–Perot (FP) nanocavity adjacent to T-shaped gap waveguide ports, spectrally selective filtering is realized. When the wavelength of incident light corresponds to the resonance wavelength of the FP nanocavity, the surface plasmons are captured inside the nanocavity, and light is highly reflected from this port. The resonance wavelength is determined by using Fabry–Perot resonance condition for the nanocavity. For any desired filtering frequency the dimension of the nanocavity can be tailored. The numerical results are based on the two-dimensional finite difference time domain simulation under a perfectly matched layer absorbing boundary condition. The analytical and simulation results indicate that the proposed structure can be utilized for filtering and splitting applications.